Among patients hospitalized for an acute coronary syndrome (ACS) or heart failure (HF), depression and anxiety disorders are common and independently associated with poor function, readmissions, and mortality. Single interventions (e.g., antidepressants) for these disorders have not improved medical outcomes, and typical clinical approaches (such as specialist referral) are poorly attended. Novel, feasible, and effective interventions are badly needed to improve clinical outcomes in this high-risk population. Collaborative care programs use a non-physician care manager and consulting psychiatrists to manage psychiatric conditions in patients with medical illness. Standard versions of these programs improve mental health but have not consistently improved cardiac outcomes. New ?blended? care models targeting both psychiatric and cardiac conditions have had promising effects on medical outcomes. However, such programs have typically managed depression in outpatients with stable cardiac illness, rather than targeting broader and higher-risk cohorts. Furthermore, prior blended care models have only included limited health behavior components in their interventions, despite the vital effects of such behaviors on cardiac prognosis. To address these limitations, we propose a pragmatic randomized trial of an enhanced blended collaborative care program. The trial will enroll 260 patients admitted to an academic or community hospital for ACS or HF who have depression or an anxiety disorder. The 26-week intervention will use a nurse care manager to engage participants in the hospital and coordinate with them by phone post-discharge. The nurse will provide psychotherapy, specifically promote health behavior adherence using motivational interviewing, and assist with medical self-monitoring (e.g., weight, blood pressure). The nurse will also transmit medication recommendations from study team psychiatrists and cardiologists to patients? medical providers, who will prescribe all treatments. Patients will thus receive expert guidance integrated into their existing medical care. The trial?s innovations include: (1) hospital-to-home care management that begins during admission and continues through the high-risk post-discharge period, (2) inclusion of patients with multiple psychiatric or cardiac conditions, (3) a flexible three-pronged (psychiatric, behavioral, cardiac) approach with a more robust health behavior intervention than in any prior collaborative care program, and (4) data collection via an iPad- internet system that is fully integrated into the clinical record to allow use of this data in patient care decisions. The program will be compared to enhanced usual care. The trial?s primary outcome measure will be physical function at 26 weeks, given that low function independently predicts new cardiac events. Our novel approach targeting multiple contributors to low function in ACS/HF patients should have strong effects on this main outcome. We will also examine group differences on additional key patient-reported outcomes and cost metrics, and we will assess the intervention?s impact on major cardiac events throughout the study period.